How to Add button to HeroCard and select the value when clicking on it

I have implemented a carousel of Hero Cards to display all the Schedules a perticular Doc can have. In the hero cards i have added a button to select a Particular schedule. Below is the code

private async Task ShowSessionsHeroCard(IDialogContext context)
    {
        var replyToConversation = context.MakeMessage();
        replyToConversation.AttachmentLayout = AttachmentLayoutTypes.Carousel;
        replyToConversation.Attachments = await GetSessionHeroCard(context);
        //replyToConversation.Attachments.Add(GetSessionHeroCard());
        await context.PostAsync(replyToConversation);
    }

    private async Task<List<Attachment>> GetSessionHeroCard(IDialogContext context)
    {
        List<Attachment> list = new List<Attachment>();
        List<CardAction> cardButtons = new List<CardAction>();
        foreach (var sessionDetails in scheduleList)
        {
            string[] session = GetSplittedDetails(sessionDetails);

            hospitalName = session[0]; //Hospital Name: {0}
            availableDay = session[1]; //Available Day: {1}
            appointmentNo = session[2]; // Appoinment No: {2}
            sessionAvailable = session[3]; // Session: {3}

            HeroCard hero = new HeroCard()
            {
                Title = hospitalName,
                Subtitle = availableDay,
                Text = sessionAvailable + appointmentNo,
                Buttons = cardButtons
            };

            list.Add(hero.ToAttachment());

        }

        CardAction getSessionValues = new CardAction()
        {
            Value = hospitalName + availableDay + sessionAvailable + appointmentNo,
            Type = ActionTypes.ImBack,
            Title = " Select Appointment "
        };

        cardButtons.Add(getSessionValues);

        string selectedAppointment = getSessionValues.Value.ToString();
        await GetSelectedAppointment(context, selectedAppointment);

        return list;
    }

     private async Task GetSelectedAppointment(IDialogContext context, string sessionSelected)
    {
        var replyToConversation = context.MakeMessage();
        //replyToConversation.AttachmentLayout = AttachmentLayoutTypes.List;

        string[] result = Utility.SplitSelectedApoitmentString(sessionSelected);
        var heroCard = new HeroCard()
        {
            Title = "Appointment Schedule",
            Subtitle = "These are the Appointment Details",
            Text = "Hospital selected : " + result[0] + "\n" + "Day of Appointment : " + result[1] + "\n" + "Time of Appointment : " + result[2] + "\n" + "Appointment Number" + result[3],
        }.ToAttachment();

        Attachment attachment = new Attachment()
        {
            Content = heroCard.Content,
            ContentType = heroCard.ContentType
        };
        replyToConversation.Attachments.Add(attachment);
        await context.PostAsync(replyToConversation);

    }

My questions are

1. Am i defining the Button Correctly?
2. The CardAction getSessionValues is getting some values even before i click on the button. How to avoid that.
3. How to get the selected card value and pass it to another method.

I cant figure out whats wrong here please help. (Am sure Am doing sumthing very stupid.)

Thanks in Advance :)